#region The MIT License
// The MIT License
// 
// Copyright (c) 2009 octalforty studios
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
#endregion
using System;
using System.Collections.Generic;
using System.ComponentModel.Composition;
using System.Diagnostics;
using System.IO;
using System.Text.RegularExpressions;

using octalforty.Componento.ComponentModel.Installation.Web;
using octalforty.Componento.Util;

namespace octalforty.Componento.ComponentModel.Installation
{
    [Export(typeof(IPackageRepositoryBrowserService))]
    public class PackageRepositoryBrowserService : IPackageRepositoryBrowserService
    {
        #region Private Fields
        private IWebRequestFactoryService webRequestFactory;
        #endregion

        #region Public Properties
        [Import()]
        public IWebRequestFactoryService WebRequestFactory
        {
            [DebuggerStepThrough]
            get { return webRequestFactory; }
            [DebuggerStepThrough]
            set { webRequestFactory = value; }
        }
        #endregion

        public PackageReference[] GetPackages(Uri repositoryUri)
        {
            Regex r = new Regex(@"^(?<PackageName>[^/][^\s]+)\s+((?<Version>\d+(\.\d+){0,3}))?\s*(?<Uri>.+)$", RegexOptions.Compiled | RegexOptions.Multiline);
            IWebRequest webRequest = WebRequestFactory.CreateWebRequest(WebRequestMethod.Get, new Uri(repositoryUri, "packages.cpri"));

            List<PackageReference> prs = new List<PackageReference>();

            using(IWebResponse webResponse = webRequest.GetResponse())
            {
                using(Stream responseStream = webResponse.GetResponseStream())
                {
                    Console.WriteLine("Downloading {0:N1} Kb", webResponse.ContentLength / 1024.0);

                    ParsePackageIndex(responseStream, r, prs);
                } // using
            } // using

            return prs.ToArray();
        }

        private void ParsePackageIndex(Stream responseStream, Regex r, List<PackageReference> prs)
        {
            StreamUtil.ReadLines(responseStream, 
                                 delegate(string s) { return r.IsMatch(s); }, 
                                 delegate(string s)
                                     {
                                         Match m = r.Match(s);

                                         Version version = m.Groups["Version"] == null || string.IsNullOrEmpty(m.Groups["Version"].Value) ?
                                             new Version(0, 0) :
                                             new Version(m.Groups["Version"].Value);
                                         prs.Add(new PackageReference(m.Groups["PackageName"].Value, 
                                                                      version,
                                                                      new Uri(m.Groups["Uri"].Value)));
                                     });
        }
    }
}